Circular knitting machine



1954 A. SHORTLAND CIRCULAR KNITTING MACHINE 2 Sheets-Sheet 1 Filed Feb. 13. 1953 1954 A. SHORTLAND CIRCULAR KNITTING MACHINE 2 Sheets-Sheet 2 Filed Feb. 13, I953 United State CIRCULARJQNITTING MACHINE Arthur Shortland, Leicester,England,'.assignor to: Mllor Bromley. & Co. Limited, Leicester, England, .a British company- Application February 13,1953', S'erialNo. 336,811

Claims priority, application-Great Britain FebrIIary-ISQ 1952- 3 Patent '0 This invention relates to knitting machines equipped with independent latch needles; and has for its-object to provide in such machines'means of"asi1"nple and'elficient character for preventing the latches of predetermined empty'needles in a set'from being'open; and thereby ensuring that those needles donot' take yarn:= and knit; ata'yarn feedinglocati'o'n; N

By an empty needle'is meant 'onewhic'h'has 'no loop around its stem" or in its-hock. Accordingly, althoughthe-invention" is applicable to any-knitting} machine f inwhich the latches of desiredemptyfineedls are- 'fdeliber'- atelyclosed to prevent saidneedles from knitting; 1s principally the intention to employthefinvention in -a machine adapted to carry outthe particular method-of knitting described andclaimed 'in our priorUhited-States Patent No. 2,442,442 that is 'to say-i'a method consisting of closing the latc'hes of needles in' a set,- thereafteropenin-g'the latches of some of 5 the needles of 'th'e set 'while the latches of the'remainin'g needles :of the set'iare lge'pt closed, and feeding yarn to'the 'needles so=thatfthosewith open latches take the yarn' and knit"-"whilst -the needles with closedlatches do not knit -'by -'reason-of ithe' yarn being prevented from entering 'the"hooks oflthose needles.

By such methods of knit-ting various conventionalst-itch' effects including; for example; pressoif, miss stitch"; and purl stitch-effects; or any desired combination cfi such effects; can be produced.

Now'whenever latches of empty lateh' needles are closed and not required to' knit-, there -is*a"-tendency; especially when using certain yarns;--foiloose or trailin'g fibres to become trapped in-fr'ont of the closed latches' and for th'ese' fibresto 'open the 'latchesscythat;contrary to requirements, yarn is takenb'y the empty'needles"at-' the next yarn feeding location. of f emptyneedles *sometimes-tend 't'o *be sh'aken atleast partially open, withthesame consequences, by reason ofthe operating buttson the saidneedles; oi on associated jacks or sliders; being joled by conta with uneven edges ofla cam racez Accordihgly; -an' aim of this invention is to overcome these diflicult-ies's The means constituting;thednventionmomprise a series of latch controlling members amounted- 1 forrmovementr independently in a carrier whic is arrangediorrarrange able:adjacent-to a needleibed' containing acsecmfilneedl'es the latches of predetermined empt-y=' OHBSSOfIi :whichiare required to be closed at a yarn feeding locationuithe said carrier being adapted to be driven in suitable timed relation: with the relative movement;- betweennthe needle bed and theassociated-cam system for op,er ating.:;the needles; and the latch. controlling members beingyselectively oper-'- able to control the latches of theaforesaid-predeterminedr empty needles of thesetc With the: knitting machine in operation; the -carrier? is so driven that the operative ends of the latchgcontrolling. move seriatim across the leading: ends:

members therein of successive needles in thesetr controlling member isselected it automatically projected 'into such: the latch of the relevant emptytneedle andpositively prevent this latch opening'iat themember in"thecarrier, on: f toremain clear of the latch of Again-, closed latches The construction and arrangement are such, moreoven. that wheneverralatch operative -.=end will be a position as to guard.

yarn feeding. locatio ng the operative end-of each non-selecte'dlatch controlling; the other hand, is permitted-- the appropriate-.needle thereby, enabling this latch, .previouslyopenedby an old 2f loop omtheneedle as the latte'r' was advanced-to clearing position, to be turned over and closed by 'the said- 106p upon Subsequent retraction: of the needle to knock-ingover positions Thus, as will b'e appreciated, when the needles of the set are-retractedseriatim to knocking-over position the fed yarn' will be taken and formed into stitches onl-y by the-needles with open hooks, --and will merely; pass tothe back of the predetermined emptynee dl es with theclosed hookss The means of this invention therefore positively prevenLthe latches of these empty needles from being-open at-the yarn feedinglocation.

In this: last regard, if the latchof an' emptyneedle happens to be partially open as the needle approach'es the yarn feeding location; then -the operative end of the relevant selectedlatch'controllin'g member will, as it is projected into its latch guardingposition and moves laterally-across the needle; contact the partially open latch and close "the same with a cumming action. Consequently, if the' causeof the latch 'being partially open is'the presence p yarnfibres," then theclosure' of the latchby the'latch controlling-member may also'resultin the 'cutt-ing -ofthe fibres by a scissor actiom Accordingly, the expression controlling used in' thisspecifi caknittingmachines-having but a single needle bed equipped" blades are disposed well clear of needle latches as the; wheel'or-drumrevolves. When selected, however, blades tiltfor cant'outwardly with respect to the axis of the: Wheelordrum-asfaconsequence of which their operative ends are movedinto latch controlling position.

The pivoted latch-controlling blades may convenientlyf be provided with operating; bntts'adapted to beact'ed uponby'blade selectingmeans of any suitable character, and relatiyely fixed cam means may 'beprovided to push back and thusrestore selected blades to their normal positions-after*they*have performed their function? In this regard, it'will lse appreciated that any. one'of the blades; when"select'ed,'- serves to control one latch onlyi for the comparativelyshort duration ofthne that the relevant" needle is passing, or is beinglpassed, by, the yarn feeding means:

The" inventionmay advantageouslyjbe applied to .a knitting'imachine equipped with means for transferring loops orstitches from certain needles to others combined With'means forclosing the-latches of needles from which the transfer has been effected. Thus, in a machinewith' a single; set of needles, the transfer may be eflectedfrom: desired needlsto adjacenttneedles, and: in amachinewith atleasttwo' sets of needles from needles in one set to needles-inthe other set. In this latter connection the latch controlling members may, where practicable, beiselectively, operated to control closed latches of-pre determined needl'es in one set 'by contactwith needlesfoftheother set selected. toknit;-

In order that the invention may be more clearly Figure 1 is a vertical sectional view of so much of such structed and operable in accordance with the invention,

Figures 2 and 3 are sectional plan views taken respectively on the lines 11-11 and 111-111 of Figure 1,

Figure 4 is a detail underside plan view, as seen in the direction of the arrow A in Figure 1, illustrating the driving disc of the latch control unit,

Figure 5 is a perspective view of one of the latch controlling blades per se,

Figure 6 is a detail side view of one of the said blades shown in relation both to an inoperative cylinder needle and a companion dial needle, and

Figure 7 is a diagram depicting a few inoperative and selected cylinder needles, shown in relation to the centre line of the rotary latch control unit, this figure serving to facilitate a description of the manner in which the latch controlling blades are selectively operated.

Like parts are designated by similar reference characters throughout the drawings.

The machine illustrated in Figure 1 includes a rotary needle cylinder 1 equipped with independent latch needles 2, and a co-operating rotary dial 3 equipped with independent dial needles 4 also of the latch type. The stationary cylindrical cam box which surrounds the needle cylinder 1 and serves to house the cam system (not shown) for operating the cylinder needles 2 is indicated at 5, whilst at 6 is shown the conventional fixed dial cam cap serving to support the cam system for operating the dial needles 4. In the example illustrated, each of the cylinder needles 2 has associated therewith a loop transferring instrument 7, and, similarly, every dial needle 4 is associated with a loop transferring instrument 8.

Immediately in advance of the yarn feeding location at each feeder of the machine, there is provided a pattern selected latch control unit which is designated generally by the numeral 9 and includes a radially tricked rotary wheel 10 arranged for rotation about a vertical axis a in a bracket 11 mounted upon the top of the cylinder cam box. Located in the vertical tricks 12 are latch controlling blades 13 the longitudinal stems 13a of which extend more or less vertically in front of the cylinder needles ments 7 associated therewith. At their upper ends these stems are formed with outwardly directed operative ends 13b which, as shown most clearly in Figures 5 and 6, extend substantially at right angles thereto and project from the tricks 12 in the wheel 10 (see Figure 1). The rear edges of the blade stems are so angularly formed as to provide thereon fulcrum points 14 about which the latch controlling blades 13 can rock. Secured to the lower end of the rotary wheel 10 by means of screws 15 is a peripherally toothed driving disc 16 arranged to meshwith the stems 2a and 7a of the cylinder needles 2 and the loop transferring instruments 7 so that as the cylinder 1 and the dial 3 of the machine rotate together, the wheel 10 will be driven from the cylinder at a commensurate peripheral speed. As illustrated in Figure 4, the screws 15 serving to secure the driving disc 16 to the underside of the wheel 10 extend through arcuate slots 17 in the said disc so that the latter, during assembly of the unit can be initially adjusted, circumferentially, with respect to the wheel. This adjustment enables the latch controlling blades 13 to be accurately set in relation to the stems of the cylinder needles. But when once this initial adjustment has been effected the driving disc is permanently fixed to the tricked wheel 10 by means of a dowel 18 driven into suitably drilled axially aligned holes (see Figures 1 and 4). tricked outer portion of the wheel rests upon the top of inwardly directed unit-supporting part 11a of the bracket 11. The lower end of the centrally bossed portion 10a of the wheel 10 is embraced by a ring 19 which serves to retain the blades 13 in the wheel and is mounted to revolve in a circular bearing hole formed in the part 11a of the bracket. The top side of the driving disc 16 is formed with a boss 16a which is spigoted into the underside of the retaining ring 19. As will be appreciated, the tightened screws 15 exert the pressure 2 and the loop transferring instru- The radially trol the latch necessary to clamp the ring 19 firmly in position between the driving disc and the wheel 10. Depending from a plate 20 which is attached by screws such as 21 to the top of an upper horizontal portion 11b of the bracket 11 is a fixed, vertically disposed bearing pin 22 which extends down into a central bore 23 formed in the boss 10a of the tricked wheel 10. As shown in Figure 1, a thrust washer 24, fixed in position by means of the screws 21 and also by an additional screw or screws such as 25, is interposed between the underside of the portion 11b of the bracket and the upper edges of the latch controlling blades 13. At their lower ends the stems 13a of the latch controlling blades 13 are formed with outwardly directed foot-like extensions 13c which project radially from the tricked wheel and at their outer extremities are bent laterally to provide butts 13d adapted to be acted upon by selected cylinder needles 2 and their associated loop transferring instruments 7.

Normally, the latch controlling blades 13 are pressed back in their tricks 12 with their butts 13d upwardly inclined as shown at the left-hand side of Figure l, and their operative ends 13b held up so as to be well clear of the latches 4a of dial needles 4 (see Figure 6). In this connection it will be appreciated from a consideration of Figure 2 that as the wheel 10 rotates, the'operative ends 13b of the blades 13 move seriatim in an arc!!- ate path across and above the leading ends of successive needles 4 in the dial 3. Each time a selected cylinder needle 2 and its transfer instrument 7 come round, however, they will act upon and press down the butt 13d of the relevant latch controlling blades 13, thereby selecting and canting the latter outwards with the result that its operative end 1312 is swung outward and down to con- 4a'of the next following empty dial needle as depicted at the right-hand side of Figure 1.

In this example, those cylinder needles which are selected" are raised to take yarn and knit at a yarn feeding location F, whilst the un-selected needles remain down at a non-knitting level. This will be clear from Figure 7 wherein alternate pairs of the cylinder needles 2 are selected and the remaining intervening pairs are un-selected. Cylinder needles 2 selected to knit are raised in two stages, viz. first from the top of the cylinder verge at the level L to the intermediate level L at which they function to press down the butts 13d of the relevant blades 13, and then from the said intermediate level to clearing height L In Figure 7 the centre line or axis of the wheel 10 is indicated at a. The stems of the needles 2 and their associated needle transferring instru ments 7 are widened to provide transfer shoulders 26. and it is the widened portions of these stems, adjoining the shoulders, which act on the blade butts 13d to press the latter downwards and inwards.

A relatively fixed return cam 27 carried by the bracket 11 is provided to press back selected blades into their tricks 12 after they have performed their function.

If desired, the stems of the blades 13 may be crimped to increase the frictional contact thereof with the walls of their tricks 12 and so prevent the blades from being too loose in the wheel 10.

The operative ends of the latch controlling blades 13 may be either straight, or laterally bent somewhat, according to requirements.

The invention includes, as a feature, a complete latch control unit per se for attachment to a machine.

I claim:

1. In a knitting machine, in combination, a needle bed, a set of independent latch needles for operation in said bed the latches of predetermined empty ones of which are required to be closed at a yarn feeding location, a carrier which is arranged adjacent to the bed, an associated cam system for operating said needles, the carrier being driveable in timed relation with relative movement between the bed and the associated cam system, a series of latch controlling members which are mounted for movement independently in the said carrier, and means for selectively operating the said members to control the latches of the aforesaid predetermined empty needles of the set.

2. A combination according to claim 1, wherein the carrier is so arranged that, when it is driven, the operative ends of the latch controlling members therein move seriatim across the leading ends of the successive latch needles in the set.

3. A combination according to claim 2, wherein the operative end of each selected latch controlling member is automatically projected into such a position as to guard the latch of the relevant empty needle and prevent this latch opening at the yarn feeding location, whereas the operative end of each non-selected latch controlling member is permitted to remain clear of the latch of the appropriate needle, for the purpose specified.

4. In a knitting machine, in combination, a needle bed, a set of independent latch needles for operation in said bed the latches of predetermined empty ones of which are required to be closed at a yarn feeding location, a rotary wheel which has radial tricks formed therein and is arranged adjacent to the bed, an associated cam system for operating the needles, the said wheel being continuously rotatable in timed relation with relative movement between the bed and the associated cam system, a series of latch controlling members consisting of relatively thin blades arranged for movement pivotally within the tricks in the wheel, and means for selectively operating the said members to control the latches of the aforesaid predetermined empty needles of the set.

5. A combination according to claim 4, wherein the operative ends of the latch controlling blades extend outwardly from the rotary wheel, the said blades being so arranged in the tricks that the operative ends of unselected blades are disposed well clear of needle latches as the wheel revolves, whilst selected blades are tilted or canted outwardly with respect to the axis of the wheel as a consequence of which their operative ends are moved into latch controlling position.

6. a knitting machine, in combination, a needle bed, a set of independent latch needles for operation in said bed the latches of predetermined ones of which are required to be closed at a yarn feeding location, a retary wheel which has radial tricks formed therein and is arranged adjacent to the bed, an associated cam systern for operating the needles, the said wheel being continuously rotatable in timed relation with relative movement between the bed and the said cam system, a series of latch controlling members consisting of relatively thin blades arranged for movement pivotally within the tricks in the wheel and provided with operating butts, bladeselecting means for action upon these butts whereby the members are selectively operable to control the latches of the aforesaid predetermined empty needles of the set, and relatively fixed cam means for pushing back and thus restoring selected blades to their normal inoperative positions after they have performed their function.

7. In a knitting machine, in combination, two needle beds, a set of independent latch needles for operation in each of said beds, means for transferring loops from needles in one set to needles in the other set, a carrier which is arranged adjacent to one of said beds, an associated cam system for operating said needles, the carrier being driveable in timed relation with relative movement between this bed and the associated cam system, and a series of latch controlling members which are mounted for movement independently in the said carrier and are selectively operable to control latches of predetermined empty needles in one set by contact with needles of the other set selected to knit.

8. In a knitting machine, in combination, a needle cylinder, a set of latch needles for operation in said cylinder, a co-operating dial, a further set of latch needles for operation in said dial, a rotary wheel which has radial tricks formed therein and is arranged for rotation about a vertical axis adjacent to the cylinder, an associated cam system for operating said needles, the said wheel being continuously rotatable in timed relation with relative rotation between the cylinder and the associated cam system, a series of latch controlling members consisting of relatively thin blades arranged for movement pivotally Within the tricks in the wheel with their stems extending in front of the cylinder needles and their operative ends projecting outwardly from the wheel over the leading ends of the dial needles, and means for selectively operating the said blades to control the latches of predetermined empty dial needles required to be closed at a yarn feeding location, the arrangement being such that the operative ends of unselected blades are disposed clear of dial needle latches as the wheel revolves, whilst se lected blades are tilted outwardly with respect to the axis of the Wheel as a consequence of which their operative ends are moved into latch controlling position.

9. A combination according to claim 8, wherein the rear edges of the blade stems are so angularly formed as to provide thereon fulcrum points about which the blades can rock.

10. A combination according to claim 8, wherein the lower ends of the stems of the latch controlling blades are formed with outwardly directed extensions which project from the wheel and are provided with butts adapted to be acted upon by selected cylinder needles.

11. A combination according to claim 10, wherein the latch controlling blades are normally pressed back in their tricks with their butts upwardly inclined and their operative ends held up so as to be clear of the latches of dial needles, the construction and operation being such that as the wheel rotates, the operative ends of the blades move seriatirn in an arcuate path across and above the leading ends of successive dial needles, and each time a selected cylinder needle comes round it will act upon and press down the butt of the relevant latch controlling blade, thereby selecting and canting the latter outwards with the result that its operative end is moved to control the latch of the appropriate dial needle.

12. A combination according to claim 8, wherein there is provided at the lower end of the rotary wheel a peripherally toothed driving disc arranged to mesh with the cylinder needles so that as the cylinder and dial rotate together, the Wheel will be driven from the cylinder at a commensurate peripheral speed.

13. A combination according to claim 8, wherein a cam box surrounds the cylinder, a bracket is mounted on the cam box, the rotary wheel being arranged in said bracket, and a fixed return cam carried by the said bracket is provided to press back selected blades into their tricks after they have performed their function.

Country Date Great Britain Dec. 15, 1936 Number 

